Furnace door frame structure



April 6, 1954 E, W, pon-MEYER 2,674,211

FURNACE DOOR FRAME STRUCTURE Filed Dec. 23, 1949 5 Sheets-Sheet l INVENTOR lEDWARD W. POTTMEYER )v MJL www E. w. PoTTMl-:YER

FURNACE DOOR FRAME STRUCTURE April 6, 1954' 3 Sheets-Sheet 2 Filed Dec. 23, 1949 I #tlf INVENTOR EDwRD W. POTTMEYER V21 /ZW April 6, 1954 E. w. PoTTMl-:YER

FURNACE DooR FRAME STRUCTURE 5 sheets-sheet s Filed Dec. 23, 1949 INVENTOR EDWARD W. POTTMEYER Patented Apr. 6, 1,9754

FURNACE DOOR FRAME STRUCTURE Edward W. Pottmeyer, Pittsburgh, Pa., assignor to Blaw-Knox Company, Pittsburgh, Pa., a corporation of Delaware Application December 23, 1949, Serial No. 134,680

(Cl. 11o- 181) 8 Claims.

This invention relates to furnace structures, and particularly to an improved fastener for doorframes for furnace structures such as, for example, water-cooled doorframes for open hearth furnaces and the like.

Furnace doorframes for industrial furnaces which are exposed to high temperatures frequently deteriorate and become useless much sooner than the body of the furnace. It is therefore necessary in most industrial furnaces, to replace the doorframes during the life of the furnace. In replacing such doorframes it is economically desirable that the furnace be maintained at or near operating temperature in order to prevent the heat losses incurred in cooling and reheating and to prevent the destructive forces set up by contraction and expansion in the furnace body itself. It has been the practice in the past when a doorframe is removed to insert the new doorframe in the furnace opening, raise it into proper register with pinch bars and wedges and then bolt it at the top to the l skewback channel and at the sides to the buckstays. This is a difficult and dangerous practice since the region of the furnace openings from which the frames are to be removed and replaced is at a very high temperature.

I have discovered that the difculties, normally attendant to the changing of furnace doorframes, may be avoided by the combination which forms the subject matter of my invention.

back channel.

weight of the frame.

Generally my invention comprises, in combination, a furnace doorframe, supporting means pivoted on the top of said doorframe, lever means pivoted on the framing of the furnace above an opening in the furnace and gripping means on the lever means for frictionally engaging the supporting means to hold the frame in position in the furnace opening. The structure and operation of my invention will be more clearly understood, however, by referring to the accompanying drawings, in which Figure 1 is a partial section through a furnace opening showing a conventional doorframe in position in a furnace opening;

Figure 2 is a front elevation of a furnace opening showing a conventional frame in position;

Figure 3 is a top plan View of a doorframe and fastener according to my invention;

Figure 4 is a section on the line IV-IV of Figure 3;

Figure 5 is a section similar to Figure 4 showing the fastener in the disengaged position;

Figure 6 is a top plan view of a dierent cmbodment of my invention.

Figure 7 is a section on the line VII-VII of Figure 6; and

Figure 8 is a top plan View of another embodiment of my invention.

Figure 9 is a partial section through a furnace opening showing a doorframe incorporating the invention of this application in position in a furnace opening. v

Figure l0 is a front elevation of a furnace opening showing the doorframe of Figure 9 in position in the furnace opening.

Referring first to Figures 1 and 2, I have illustrated va conventional Water-cooled doorframe I0 and integral skewback channel cooler II in place in an opening I2 in a furnace (only partially shown). The doorframe is fastened to the skewback channel I3 of the furnace by means of bolts I4 which pass through lugs I5 on the top of the doorframe and lugs I6 welded to the skew- A wedge I1 is driven beneath the end of each leg I8 between the leg I8 and the breastplate I9 of the furnace so as to hold the door in position while the bolts I4 are inserted and to relieve the bolts of a part of the The sides of the doorframe may be fastened to buckstays 2|) of the furnace, as partially shown in chain line in Figure 1, by bolts 2I which pass through wing plates 22 on either side of the doorframe. The conventional manner of installing such a doorframe is to bring the frame to the furnace and rest it upon the breastplate I9 between the foreplate 23 and the furnace body. The upper end of the frame is next moved into contact with the skewback. The frame is lifted into registry with the furnace opening by means of pinch bars and wedges I1 driven beneath the legs I8 and finally, the frame is bolted to the skewback channel I3 or buckstays 20 as shown in Figures 1 and 2.

In Figures 3, 4 and 5, 9 and 10 I have illustrated a doorframe and fastening means according to one embodiment of my invention. A supporting arm 25 is fastened to a shaft 2B pivotally mounted on the doorframe I0 by means of a holding member 21 welded to the frame and having an opening 28 through which the supporting arm 25 extends. `A pair of lever arms 29 are fixed to a shaft 30 which is rotatably mounted in a base 3| which is in turn xed to the skewback channel I3 above an opening in the furnace. A pair of square bars 32 are mounted for rotation between the lever arms29. When it is desired to insert a doorframe including the combination of my invention it is only necessary. to place the doorframe before the opening in the furnace and then insert the supporting arm between the square bars 32 which are rotatably mounted between the levers 29. 'Ihe doorframe is then raised into position in the opening during which time the supporting arm 25 passes between the bars 32 in contact with them. When the doorframe is released from the lifting force the squarer bars 32'engage the supporting arm 25 by fricticnal engagement and hold the doorframe in position in the furnace opening as shown in Figures 4, 9 and 1G.

In Figures 6, 7 and 8 I have illustrated other and different embodiments of this invention. In

the edges of a quadrangular openingf33 adj'acent the end of a solid lever arm 34 which is fastened to a shaft 35 pivoted in baset.vv InFigure 8 4I cooled doorframes of Vthese-,called archless'type it is to be understood that' it may be used' with other types of furnace doorfrarnes and'may be otherwise embodied kwithin the scopebf the'following claims.

I claim:

l. In combination,` a furnace: havingaframe and a vertical furnace wall 'with Lanropening therein,L a furnace doorframeiitted'against said: wall in registry with said opening;supportingl means pivoted cn thetopof'said doorframe-for movement in a generally vertical v planesubstantially normal to the-'furnace wall,-lever meansr pivotally attached tothe furnace' frame above the furnace wall openingfor movement generally in substantially the vertical plane ofthesupporting'.'

means, and grasping means onA saidlever means frictionally engaging `the supporting /mea-ns to' hold said supporting means when the angle between the said supporting means and-said lever means facing said furnace wall-is greater than 95 thereby to hold the do'orframein position against the verticalA wall in "the `furnace opening.

2. In combination, a furnace having a'frame` and a Vertical furnace wall With'a-nopening therein, a furnace `doorframe fitted against said 'wall in registry with said opening, at leasttwosupporting members pivoted-onthe vtop ofsaiddoorframe for movement `generally in'substantially parallel vertical planes substantially'normal to the furnace wall, lever arms corresponding in number and spacing to the number of-supporting members pivotally attached to the frame-above the furnace wall opening for movement generally in substantially the vertical plane of the supporting members-and grasping'meansron the lever arms frictionally engaging the corresponding supporting means to hold-'said supportingmembers` when the angle between said supporting members' and lever arms facing said furnace wall is greater than 90 thereby to holdthe `doorframe in'position against the vertical Wall in. the furnace opening.

3. Inicombination, a.furnace having aiframeV and` a ,vertical furnacezswallywith an opening therein. a furnaceH dobrframe ftte'd :against' said wall in registry with said opening, at least two supporting members pivoted on the top of said doorframe for movement generally in substantially parallel vertical planes substantially normal to the furnace wall, lever arms corresponding in number and spacing to the number of supporting members pivotally attached to the frame above the opening in the furnace wall opening for movement generally in substantially the vertical planes of the supporting members, the free end of--each of the lever arms having an aperture through whichr the corresponding supporting member passes vertically, said apertures permittingthe-supportingrmember to slide freely therethrough when the door frame is raised and frictionallyengaging 'said member when the doorframe is lowered :to a point where the angle between the supporting members and the correspondinglever arms facing the furnace wall exceeds 4; In combination, .a furnace havingv a frame and a'vertical yfurnace wall with an opening therein, a furnace doorframe fitted against said wall in registry with'saidropening, at least two supporting members of substantially cuadrangu-` lar cross section'pivoted on the top of said'doorframe for'movement infsubstantially parallel verticalplanes substantially normal to the furnace wall, lever arms corresponding in number and spacing'to the number of vsupporting membersr pivotally attached to the frame above theopen'- ing in the furnace wall openingfor movement generally in substantially'the vertical planesof the supporting members, said lever arms each having a substantially 1 rectangular aperture in the free end thereof throughfwhich the supporting member passes vertically, said aperture permittngitlie `supporting member to slide freely therethroughwhenthe doorframe is raised and frictionally 'engaging' said member when the doorframe is lowered to a point where the angle between the supporting members and the corresponding lever arms facing the furnace wall exceeds 90..

5.-:[n combination, a furnace having a frame and a vertical furnace wall with an opening therein, a'furnace doorframe fitted against said wallfin registry `with saidfopening, at least two supporting members of substantially circular cross section vpivoteolon the top of `said doorframe for-.movement in substantially parallel vertical planes substantially 'normalto the furnace wall,

lever-arms corresponding in number and spacing tothe numberl of supporting members pivotally -attached to the frame above the opening in the furnace wall openingfor movement generallyin substantially the 'vertical plane, said lever members each having a'substantially circular aperture inthe `free-end thereof through which the supporting member passes vertically, said aperture permitting the supporting member to slide freely therethrough when'the doorframe is raised. and frictionally engaging said member when the doorframe is lowered to a point where an angle Abetween said supporting members'and lever arms facing :said furnaceiwa-ll isigreater than 90'.

and :a V.vertical furnace wall withV an opening,

therein, a furnace doorframe fitted against saidlY wall in registry lwith saidfopening, at least two supporting members pivoted on the top of said doorframe'V for movement generally in substantially parallel vertical' planes substantially normalfto.` the furnace/wall; lever` armsf corresponding in number and spacinglto'fthe number'fof'suplporting members pivoted at one end of the frame above the opening in the furnace wall opening for movementI generally in substantially the vertical plane, each of said levers having an opening in the end opposite the pivot, said opening admitting a supporting member vertically, gripping means pivoted adjacent opposite sides of said opening to lie on opposite sides of the supporting member, and said gripping means permitting the supporting member to pass freely therethrough when the doorframe is raised and frictionally engaging said member when the doorframe is lowered to a point where an angle between said supporting members and lever arms facing saidI furnace wall is greater than 90.

7. A combination as claimed in claim 6 in which the gripping means are a pair of square bars pivoted so as to engage opposite sides of the supporting member.

8. A combination as claimed in claim 6 in which the lever arms comprises a pair of side` members attached at one side to a shaft which isl pivoted to the furnace frame and the gripping means are a pair of square bars pivoted between the ends of the side members remote from the pivot so as to engage opposite sides of the supporting member.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 238,411 Lowell Mar. 1, 1881 1,044,130 Brown Nov. 12, 1912 1,529,193 Lewis Mar. 10, 192@ 1,580,187 Williams Apr. 13, 1926 1,792,947 Watson Feb. 17, 1931, 1,831,461 McAfoos Nov. 10, 1931 

